1. Field of the Invention
This invention relates to containers for compressed gases, and more particularly for containers which may be carried on a person.
2. Related Art
Divers, fire fighters, miners and alike must perform numerous tasks which require that they carry a portable supply of compressed gases. These gases are usually for breathing in unbreathable environments; however, other gases such as carbon dioxide which are used for extinguishing fires are also carried.
Conventional containers for this purpose are normally of a cylindrical shape with domed ends, and construction is usually of steel or aluminum, or glass fiber wound aluminum. Unfortunately, these containers are cumbersome to wear due to their bulky shape, their ridged structure and their relatively heavy weight. As a result, wearers have difficulty moving in confined spaces, are uncomfortable and are subject to increased levels of fatigue.
Prior approaches such as seen in U.S. Pat. No. 3,338,238 involves a complex, multicell container which can be made in a relatively flat, oval-shape cross section. However, these containers are difficult to manufacture and do not conform to the shape of the wearer.
U.S. Pat. No. 3,491,752 illustrates a slightly flexible pressure vessel made in the form of a coiled spiral tube. This vessel is compact and light weight, but ineffective if more than several minutes of breathing gases are required. While the storage capacity of such a pressure vessel could be increased by using either larger diameter tube or thicker walled tube, the changes are impractical since tubing of increased dimension would not easily coil into a compact shape. U.S. Pat. No. 3,432,060, to the same inventor has similar deficiencies.
U.S. Pat. No. 1,288,857 illustrates a life preserver with a plurality of closed cylinders constructed of rubber, rubber cloth or other suitable air tight fabric, the cylinders being connected together by smaller tubes which are preferably integral with the cylinders. However, the shape, size, and requirement for connecting pipe sections make the unit expensive to manufacture. Further, because of the need for connecting tubes, etc., it cannot be as compact as desirable for personal use.
U.S. Pat. No. 2,380,372 illustrates a flexible, portable container designed to be built into the seat of a parachute that is part of a parachute pack in order to provide oxygen to parachutists. The container includes a length of pipe made in the form of a flat coil, the outer turns of which conform generally to the shape of the seat. The coil of pipe is in the form of a coil in ever decreasing rectangles, squares, or circles which are concentric.
U.S. Pat. No. 1,608,267 is patent which has a life-ring worn around the waist of a user and has a supply of air therein.
German Patent No. 971,689, issued in 1959, includes a plurality of parallel metal cylinders, connected to succeeding cylinders by means of small metal tubes. This particular device is obviously expensive to make and very heavy to wear.
It will be appreciated that the prior types of portable containers had the following disadvantages:
1. If the containers hold more than a few minutes worth of breathing gases, they are large in size and protrude a great distance from the wearer's body. This makes movement through the water or small spaces extremely difficult.
2. Containers designed to hold high pressures are not normally highly flexible. Nonflexible containers do not contour to the wearer's body and are uncomfortable to wear.
3. Containers in use at the present time are normally relatively heavy.
4. The manufacture of existing containers is complex and costly.